Encoder
by SapphireClaw
Summary: Tadashi didn't believe in ghosts, but it was hard not to when he was all the proof he needed. After he dies in the fire at SFIT, he finds himself unable to be heard or seen by his grieving loved ones. Only later on did he find out that he wasn't as helpless to comfort his family as he thought. He was starting to learn that he could interact with the living in a very... unusual way.
1. Chapter 1

**_**Ok, so I know what my followers and regular readers are probably thinking: "_** **Sapphie?! What the hell is this?! You haven't updated any of your other fanfics in months yet you decide to slap us with a Big Hero 6 fanfic?! What happened to all the FMA?** ** _" Well I say NO! I NEEDED A BREAK FROM ALL THE FMA ANGST AND SHIT SO WHAT DO I DO? I write an equally as sad Big Hero 6 fanfic, that's what I did. What can I say? That movie was fucking awesome and it woN'T LET ME GO GODDAMN IT HELP ME. Anyway, so here's a ghost!Tadashi fanfic because that nerd didn't deserve to die but there are lots of alive!Tadashi fanfics already out there. Yes, I know there's a bit of a surplus of ghost!Tadashi fics as well, but this one is a lil different, I promise! At least I hope it is. Maybe once I complete this thing BH6 will finally let me rest!**_**

 **Anyway, just to make this clear! This is NOT a Hidashi fanfic! Everything here is purely innocent brotherly love! (Also this chapter was rushed so it may be a little poopy) With that, I hope you enjoy this fanfic!**

* * *

 _"For everything that could have been, at least we took the ride. There's no relief in bitterness, might as well let it die."_

 _(Pendulum –Encoder)_

* * *

 _Someone has to help_.

Tadashi Hamada could hear his little brother calling after him as he ran. He didn't want to ignore Hiro, but he had to go. He had to save his professor, his mentor, his borderline father-figure. He'd never forgive himself if he didn't try.

Tadashi threw open the doors to the burning building and felt the rush of blazing heat. He paid it no mind as he dashed inside, still hearing the cries of his baby brother.

"Professor Callaghan!" He shouted hoarsely as smoke filled his lungs. "Professor, where are you?!" The young man continued to call out as pushed his way past flames and debris, struggling through the wreckage.

He heard a thunderous boom and turned his head to look, but a sudden wave of excruciating heat washed over him, then a blinding flash of light...

Then there was nothing.

* * *

Tadashi woke with a gasp, breathing heavily as if he had just run a mile. He stared up at the blackened spires of twisted metal that had once been a roof. There was thick smoke in the air but the flames seemed to have calmed.

With a groan, the young man pushed himself up to sit and looked around. There was still fire burning around him, but judging from the violent stream of water being pumped into the building from nearby, the firefighters were working on it.

Tadashi had the weird feeling that he was forgetting something, but he brushed it off. He shakily stood from the ground and took a stumbling step forward. The young man slowly made his way toward the nearest exit, which was a gaping hole in a wall a short distance away.

Only one thought filled Tadashi's mind: "I have to find Hiro."

Paying the firefighters just outside the building any mind, the man stumbled out and down the steps. He saw the flashing lights of a couple ambulances in the dark and walked toward them, dread pooling in his gut. Was Hiro okay? Did he get hurt?!

Tadashi practically ran to the ambulances and frantically looked around at the paramedics that rushed to care for the injured. He quickly spotted the messy black hair of his baby brother. Hiro was sitting in the back of an ambulance with a blanket wrapped around his shoulders and a styrofoam cup in his hands. He stared down at whatever drink was contained in the cup, his eyes wet with tears and his expression lax.

"Hiro!" Tadashi shouted. He ran over to his brother and scanned him for injuries. "Are you okay? Are you hurt?!"

Hiro seemed to ignore him and just continued to stare at his drink. Tadashi grew increasingly worried at his brother's silence and opened his mouth to ask again, when he heard a frantic voice call out behind him.

Tadashi turned around and saw his Aunt Cass rushing toward them with tears streaming from her eyes. "Hiro!" She sobbed.

Tadashi quickly tried to move out of the way so their aunt could see that Hiro. He wasn't fast enough, the man only gave a sharp yelp when the woman ran right _through_ him, leaving him feeling violated and out of breath as if the air had been sucked out of his lungs.

Tadashi's heart stopped dead in his chest and his eyes widened. " _No_." He choked, spinning around to stare at his Aunt who was now hugging Hiro tightly and crying into his hair. "Aunt Cass!" Tadashi called desperately, stepping toward his brother and relative. "Please, answer me!"

No response.

Tadashi reached out a hand and frantically swiped at the huddled Hamadas, staring in horror as his arm passed right through them as if they were nothing but thin air.

" _No!_ " The young man shouted hysterically, his heart thundering in his ears and his mind clouded by horror. " _This isn't real! I must be dreaming_!"

Loud, heart-wrenching sobs broke Tadashi from his frantic thoughts and attempts to touch Cass. He looked down at his little brother and saw him hugging their Aunt back with tears streaming down his cheeks as his shoulders shook with sobs.

"He can't be dead!" Hiro cried out in a broken voice. "T-Tadashi wouldn't just leave me! H-He _can't be gone_!"

Aunt Cass held her nephew tighter and tried to hold back her own sobs for the sake of the boy in her arms. "I'm so sorry, honey," She choked, tears falling from her eyes onto Hiro's hair as they both cried.

Tadashi felt as if an icy hand was squeezing his heart until it was sure to pop. He had tried to convince himself that he was wrong, that somehow this was all a dream, but he knew, with a cold weight in his chest, that it was true. He was dead. He was a ghost. No one could see or hear him. He had died in the fire. _And_ _Hiro watched it happen_. He made his baby brother watch him die of his own idiocy and leave him all alone. Hiro was alone.

And it was all his fault.

* * *

 ** _**sorry for the shortness of this chapter, but the next ones will be a bit longer, I promise._**

 ** _Please leave some feedback of whether or not you liked this! I'm not sure if I should continue if it isn't something you guys would want to read!**_**


	2. Chapter 2

**_**(SUP NERDS! I have returned with the next chapter of Encoder! (Don't get used to such frequent updates, I'm only posting this because I'm going to be gone for a week!) I forgot to mention in the first chapter's author's note that the title of this fic is also the title of my most favorite songs from the band Pendulum, which is why I used it for the fic. Because it's awesome. Look up Pendulum if you think you'd like drum n' bass, there isn't a song by them that I don't like._**

 ** _Anyway, this chapter was supposed to be half this length, but I decided to add what was supposed to be chapter three to it. Bring tissues and enjoy!)**_**

* * *

 _"So let's dim the lights, get a case out, pack up your pride. It's over, we're out of time. Believe me, I'm on your side."_

 _(Pendulum –Encoder)_

* * *

Everything had taken on a dream-like quality for Tadashi. Sounds were muted and distant, his sight blurred around the edges. He could only watch as his little brother shut down.

Hiro had only cried for a few minutes in Aunt Cass' arms. Then he just fell quiet and stared off into space with glazed eyes. It hurt Tadashi to see his baby brother this way, but he himself had shut down as well. He could only follow blindly as Aunt Cass lead Hiro to her car after the paramedics checked and deemed him uninjured and only suffering from shock.

Tadashi walked into the backseat of the car, noticing that he could move through objects with a detached air, and watched Hiro through the rear-view mirror as their Aunt began to drive. The boy leaned, limp against the window, staring out at the bright lights and buildings as they passed. His eyes were dazed and lifeless and Tadashi felt a pain in his chest at the sight of them.

The older Hamada didn't even realize that the car had stopped until Hiro's door opened and Cass coaxed him out. Tadashi walked through the car door and followed the two as they entered the Lucky Cat Café and climbed the stairs, Cass murmuring comforting words to Hiro the whole way.

The woman lead the boy to his bed and tucked him in. Hiro just blinked up at her with clouded eyes. Tears slipped from her own eyes and she gave her nephew a hug, whispering, "It'll be alright, sweetheart. We'll get through this..."

With one last kiss on Hiro's forehead, their Aunt left, glancing back with grief-stricken eyes. The door closed with a soft click and the room was plunged into silence.

Then the quiet sound of sobbing floated through the air, sounding broken and tiny. Tadashi's heart shattered and he felt tears welling in his eyes as he watched his brother's small form tremble beneath the blankets.

 _This is all my fault.._. Tadashi thought as he fought back his own overwhelming urge to cry. _I should have never ran into that building. I tried to be something I wasn't and because of that, Hiro had to watch me die. I'm no hero, I'm just a horrible older brother..._ The young man couldn't hold back his tears any longer and silently cried as he watched his little brother sob himself to sleep.

Hours passed and Tadashi found himself sitting on the computer chair in the middle of the bedroom and watched his brother sleep with a heavy heart. With a frustrated sigh, the man stood abruptly, the chair spinning in the wake of his movement. Tadashi froze and looked back at the wheeled contraption. He slowly reached out and touched the desk chair again, pushing lightly. It moved. He looked down at his hand and clenched it into a fist. So he could touch inanimate objects but not living people? How cruel.

His train of thought was cut off at the sound of sobs. Tadashi turned his head and looked back at his brother. Hiro was tossing and turning in his bed, tears streaming from his closed eyes, chest heaving in tiny, quiet sobs.

"Don't... Don't go... Please..." The boy whimpered, fear permeating his voice.

Tadashi's heart broke at the sound of his little brother's cries. He rushed over to the bed and looked over Hiro, hands outstretched yet hesitating just over the boy's body. He withdrew and stared helplessly down at his brother, wishing with all his heart that he could touch Hiro. Instead, he reached a hand out and stroked the boy's wild mop of hair, though he wasn't actually touching it, and hummed a lullaby, begging to whatever God that was out there that Hiro would be comforted.

Miraculously, the boy's tremors stilled and he fell silent. With a sigh, Hiro shifted his body closer to his older brother's spirit, murmuring, "Tadashi..."

Tadashi smiled to himself and felt a few tears fall down his face. "Y-Yeah, kiddo..." He whispered. "I'm here... I'll always be here... I promise."

The older Hamada stayed like that the whole night, comforting his little brother until dawn.

* * *

Tadashi's funeral was held a day later. It was a depressing affair, full of mourning friends and family. It even rained and Tadashi couldn't help but scoff at the cliché.

It was strange, knowing that he was watching his own funeral. It would have been even more strange if his body was actually being buried, but it was never recovered from the fire. It was probably nothing but ash anyway.

After the funeral, everyone went back to the café for refreshments and condolences. Tadashi simply followed along, hovering worriedly behind his unusually silent little brother. His worry grew when Hiro didn't pay any attention to those around him. He only walked past them, ignoring their pitying gazes, and slowly climbed the stairs to the bedroom.

Tadashi simply followed the boy into their room. _Though_ , he thought miserably, _I can't really call it our room anymore. It's just his now_...

Hiro paused in the middle of the room and just stood silently. Tadashi began to worry and moved closer to his little brother, though he knew he couldn't offer any comfort. The boy's bowed head slowly raised, and turned toward the rice paper partition between his side of the room and his big brother's.

Hiro began walking toward Tadashi's side with heavy, sluggish steps. His shoulders were hunched as if he held the weight of the world on his back as he slowly slid the partition aside. His brother's shelves and bed were clean and neat, just as Tadashi had left it before they went to the showcase. The only difference now was the baseball cap that sat in the center of the immaculate bed.

Hiro stood still for several moments, just staring at his big brother's room. Then, he slowly shuffled forward and stopped next to the bed. The boy stared at the baseball cap sitting innocently on top of the blankets with glazed eyes. Tadashi hovered nearby, worrying over his little brother's emotional state.

The younger Hamada slowly reached out a shaky hand and gingerly picked up the well-worn hat. He gently ran a thumb over the San Fransokyo Ninjas logo stitched on the front, staring down at the hat with an unreadable expression.

Suddenly, Hiro let out a choked cry and clutched the baseball cap to his chest, tears streaming down his face. Tadashi gave a start from where he stood next to his baby brother. The young man felt his heart break in two as Hiro's body shook the weight of his grief, wishing with his entire being that he could just touch his little brother. Hug him and hold him and tell him it was going to be all right. But he couldn't. And that was what hurt most.

With a particularly violent sob, Hiro collapsed onto Tadashi's bed. The boy curled up on top of the blankets, clutching his big brother's favorite hat to his chest as he released the misery and soul-tearing grief bottled up inside of him.

Tadashi could only watch with tears in his eyes as his little brother broke down once again.

* * *

 ** _**(MANY MUCH SADS! Hiro is rekt. So next chapter will start off sad as well (with a very familiar context ;3) but, like the summary of this fic suggests, Tadashi learns how to 'ghost' better and in different ways. Yea!)**_**

 _Leave a review if you liked what you read!_


	3. Chapter 3

**_**(Yeah! I found Internet access so now I can post! I'm in Nauvoo Illinois right now. It's so pretty and the Mississippi is so freaking huge! It's also really hot. And humid. It sucks (especially for someone who lives in a place that's dry as a bone). Anyway, here's chapter 3! It starts out like that one scene from the movie but diverges from the storyline here in a bit. Also, Baymax is bae. I just wanted to say that.)**_**

* * *

 _"So let's dim the lights, when you take me out on your sights. We're spinning out of sight. Believe me, I'm on your side."_

 _(Pendulum –Encoder)_

* * *

For the next two weeks, Hiro was practically nonexistent. He hardly ate, he hardly slept, and he hardly ever left his room, much to the worry and sorrow of the ghost of his brother who watched him, day in and day out. Tadashi was currently sitting on his bed, gaze following his Aunt as she left the room after murmuring soft words to Hiro and leaving a plate of breakfast.

The boy sat in a bean bag and stared at Megabot, absently stroking the smooth black magnets with his thumb. With a sigh, Hiro stood and took a step toward his bed, only to have a part of his robot detach and fall onto his foot.

"Ah!" Hiro gasped, hopping on one leg as he held the other. Tadashi stood up worriedly as his brother stumbled over to his bed and sat down, bringing his foot up onto his leg to examine his toes. "Ow..." He hissed.

A series of beeps sounded near Tadashi and the ghost looked over in surprise as Baymax suddenly inflated next to his bed. Both he and Hiro stared as the robot blinked and clumsily began maneuvering himself from the small space and into the room. Once he was out in the open, he stepped toward Hiro and gave a circular wave.

"Hello. I am Baymax, your personal healthcare companion. I was alerted to the need for assistance when you said 'ow'. What can I do for you, Hiro?" The robot said.

Hiro stared at Baymax for a moment before shaking his head. "Hey, B-Baymax. I didn't know you were still active..."

Baymax's chest lit up with the familiar pain scale chart. "On a scale of one to ten, how would you rate your pain?" He asked.

Hiro sighed and shook his head, looking slightly annoyed. "A zero? I'm fine, Baymax. You can just go back to your case."

Ignoring the boy's command, Baymax leaned closer to Hiro and reached his arm down towards his toe. "Does it hurt when I touch it?" He asked while Hiro tried pushing his arm away.

Tadashi cracked a smile and let out an amused chuckle from where he stood by the bed on his side of the room, watching his creation's antics.

Suddenly, Baymax turned away from Hiro and looked straight at Tadashi, who stared right back in shock. The robot blinked and tilted his head. "Tadashi." He said.

Hiro stiffened and his slight amusement fell into grief immediately at the mention of his brother. He followed the robot's gaze to his brother's empty side of the room. With a sigh, the boy stood and went to close the divider. "Tadashi's gone, Baymax. He's dead." He mumbled.

Baymax tilted his head, confused, as he watched the ghost of the elder Hamada pass through the rice paper screen and step into the room. "Tadashi is here." He stated firmly, eyes still focused on the spirit.

Hiro sighed, looking frustrated. "No he isn't, Baymax." He growled, stalking over to his bed and sitting down. "He's dead..."

Baymax turned away from the rice paper partition and focused his eyes on Hiro instead of Tadashi. He scanned the boy again and was concerned with the result. "Your neural transmitter levels are decreasing. I apologize for upsetting you, Hiro." He waddled over to the boy and stood in front of him. "You are my patient. I would like to help. However, My creator has not programmed me with a database of personal loss treatments. I feel that it'd make me a better healthcare companion if you download a database onto my memory chip." The bot asked, voice ever gentle and smooth.

Hiro was about to refuse. Why would he update Baymax if the robot were only to use the information to bother him? Then the boy felt a pain in his heart as he recalled that Tadashi had made Baymax to help people and heal the sick. If he refused to download the database only for his own wants, he'd be dishonoring his brother's hard work...

Hiro sighed and tried not to think of Tadashi. "Fine, Baymax..." He mumbled, getting up off the bed and ambling over to his computer. "I'll help you."

Tadashi watched as his creation made his way to his little brother's side, smiling sadly. At first he felt like protesting against Hiro messing with Baymax, but he remembered that his voice was no longer heard. Who knows? Mane Baymax could help Hiro with his grief.

Tadashi's expression softened and he watched as Hiro slowly opened Baymax's access port and removed the healthcare chip, glancing at his older brother's name with grief and sadness in his eyes, before quickly looking away and moving to insert it into his computer.

Baymax didn't deflate when the chip was gone, only became frozen and did not move. He was practically turned off now, but his mechanisms were still activated and powered, only they were receiving no signals to function without an artificial intelligence program.

Tadashi silently walked over to his deactivated creation and smiled. "You're going to look after Hiro, right Baymax? Protect him for me?" The young man asked, knowing well that Baymax couldn't hear him, but he felt that he should say something to him. The ghost reached out an intangible hand to place it on the bot's inflated vinyl arm. "I promise to keep watch if you protect him. Okay, Baym- WOAH!"

Suddenly, Tadashi's world was flipped upside-down and he felt as if an invisible hand had reached out and pulled him forward. With a dizzying rush, the teen was thrusted into a black place. With a few blinks, he realized that the darkness wasn't a _place_ , but his vision fading into view. He saw that he was standing directly behind Hiro, about three feet from where he'd been standing no more than two seconds ago.

With a start, Tadashi realized why.

He was _inside_ Baymax.

* * *

 ** _**(There ya go! Tadashi finds out that he can do shit! Yeah! (And now Baymax is double Bae) But you gotta wait for next chapter to see what it is he can do. Sorry._**

 ** _Also, I need to say something! There's another fanfic where Tadashi's spirit kind of attaches itself to Baymax (it's called 'Tadashi Is Here' by IAMGinny), but I assure you my fanfic is different and is in no way influenced by IAMGinny's fanfic. I started writing this months before that one was published. The other fic is really good though, and you guys should check it out! I just wanted to clear that up just in case someone thought I was being a lil idea stealing shit.)**_**

 **(As a side note, I was wondering if you guys think it would be cool to incorporate something from the song that this fic is named after. Like maybe have a line of lyrics from the song (or other songs from the same band) at the beginning of the chapter? Idk, I just thought that I should do something else with the song and not just name it after it.)**

 _Anyway, don't forget to review!_


	4. Chapter 4

**_**(ok so I revised this chapter so many fucking times it's not even funny. I don't like how it came out and it makes me angry. Oh well. Maybe you guys will get a kick out of it._**

 ** _(Also I added the lyrics to the song this is named after in previous chapters! There will be three quotes per song, so this chapter does not have the lyrics from Encoder, but the song used in the next three chapters is also a really freaking awesome song.)_**

 ** _Warning: Fluffy McFluffington the Third.)**_**

* * *

 _"In the trail of fir_ _e, I know we will be free again. In the end we will be one. In the trail of fire, I'll burn before you bury me, so set your sights for the sun."_

 _(Pendulum –Pro_ _pane Nightmares)_

* * *

Tadashi tried not to panic, he had to stay calm. Sure, he had no idea why he was suddenly seeing through his robotics project's eyes, but freaking out about it wouldn't accomplish anything. So instead he decided to try to think rationally about this. About whether or not he was actually in Batmax's system or if he only passed through the bot's vinyl exterior on accident and was only standing inside him. Tadashi didn't know which one he hoped for.

Finally, after taking a deep breath, Tadashi experimentally moved his limbs. Sure enough, he saw Baymax's round arm move into his vision. So he was actually controlling Baymax. How was that even possible? He'd have to figure that out later, but for now he had to make the most of having a tangible vessel before his chance was gone.

Tadashi looked up at Hiro and reached out hesitantly. The inflated vinyl finger poked Hiro in the back and he felt a thrill of emotion at being able to actually _touch_ his brother. However, his moment of happiness was short-lived, as Hiro spun around in his chair to stare at the nurse bot with wide eyes.

"Baymax?!" Hiro exclaimed. "You aren't supposed to be able to move without your chip!" He narrowed his eyes at the bot, somewhat freaked out, yet intrigued. "How are you still running? You have no AI. That chip was what made you _you._ How can you be controlling yourself on your own?"

Tadashi didn't know the answers to Hiro's questions. Instead, he opened his mouth, though nothing actually happened since Baymax didn't posses a mouth at all, and spoke with an actual voice, even if it wasn't his own, for the first time in more than three weeks.

"Hiro."

The younger Hamada nodded, still studying the bot curiously. "Yes... That's my name. But how did you know? That chip has all of your memory storage... You shouldn't _know_ anything at all."

Tadashi hardly even heard what his little brother had said, he was instead trying to contain his excitement. He could _talk_.

"Hiro!" He said again, with more urgency this time. "Hiro, it's me!" Tadashi reached out a balloon-like arm and placed it on Hiro's shoulder. "It's me! Tadashi!"

Hiro's eyes widened and he leaped away from Baymax. "What?! No! You're malfunctioning!" He exclaimed, breathing hard.

Tadashi belatedly realized that he probably shouldn't have just gone out and told Hiro who he was. Now his little brother was freaking out. But Tadashi refused to let this chance slip though his fingers. "No, Hiro! It's really me! I've been here you since the fire and you never were able to see or hear me, but somehow I can speak to you through Baymax!" He said excitedly, stepping toward his brother. "Oh Hiro, it's so great to finally be heard... I have so much to say to y- Um... Hiro?"

Tadashi silenced his rant to worriedly stare at his little brother through Baymax's hyper-spectral camera eyes. The younger Hamada looked pale and about ready to pass out. He was hyperventilating and clutching at the desk for dear life as his legs shook.

Tadashi reached an arm out in case he had to catch his brother. "Hiro, are you okay?" He asked worriedly. "Calm down, knucklehead. just take a deep breath, all right?"

Hiro nodded shakily and drew in a few breaths. Soon his legs stopped trembling and he nodded his head again. "I-I'm okay..." He whispered, voice scared and shaky.

The older Hamada watched worriedly as his brother slowly walked over to his bed and sat down. With a sigh, the boy scrubbed at his eyes and shook his head. He then looked up and saw Baymax's body still staring at him.

"You're still there... I'm not going crazy... Am I?" Hiro mumbled to himself.

Tadashi shook his head and he walked over to stand in front of Hiro. "No... No, you're not crazy, Hiro. I'm really here." He paused and shook his head again. "Well, not physically here... But... My soul is still out and about, I guess." He chuckled.

Hiro lowered his head into his hands. "So you're a ghost?" He mumbled in disbelief.

Tadashi blinked. "Well... Yeah... I guess so."

"But how do I know that's true? How do I know that I didn't just finally snap or something?" The younger Hamada asked tiredly.

Baymax's head shook and his eyes seemed to soften despite them being hard, pitch black cameras. "You haven't snapped, Hiro." He said gently, moving closer to his little brother and placing an inflated vinyl hand on the boy's back. "I've been here the whole time since the fire, actually. I just didn't know how to get you to hear me. But now I can! I can finally help you like I should have been all this time. It hurt so much to see you like that... To see you cry..." Tadashi trailed off and tried to banish that thought. Now was not the time to be thinking of his little brother's depression.

Hiro only seemed to curl up tighter, fingers tangling in his messy hair and tugging. " _How_ are you here? How are you talking through Baymax if you're a... a ghost?" He asked hoarsely, trying to wrap his head around what the supposed spirit of his big brother was saying.

Tadashi grew worried about how much this was affecting his little brother. He was just so excited to talk Hiro. It was probably too much to take in, but he thought that it would be best to get it all out there and answer all of Hiro's questions. "I don't know... I just touched him and suddenly I was seeing through his eyes... But I touched him before and nothing happened. Maybe it has to do with the chip?" He mused before his voice dropped off and he was lost to his thoughts.

Hiro looked back up at Baymax's body and just stared. He couldn't believe what the bot was saying. How could Tadashi's spirit still be here? Hiro didn't even believe in ghosts! But... There was no other explanation... Tadashi was here.

Suddenly, Tadashi's thoughts were cut off when Hiro threw himself off the bed and into his- _Baymax's_ body. After stumbling back a few steps, Tadashi was able to regain his balance. He stared down at his little brother, who had his arms wrapped as far around the inflated bot's stomach as they could reach and his face pressed against the vinyl.

It was odd... Tadashi could feel Hiro through the thin material, but only faintly. The vinyl was a special blend that had weak conductive properties so the bot could feel pressure. The only reason that Tadashi had built him with it was so Baymax could tell when he was touching something and to know how much pressure to use when handling patients. Now, however, Tadashi wished he had designed the robot with fully conductive skin so he could actually feel his little brother's embrace.

Those thoughts ceased when Tadashi felt a sensation of a different kind. He looked down and saw tears leaking from Hiro's eyes onto the vinyl. With a start, Tadashi realized that the boy was beginning to sob.

"Oh no, Hiro. D-Don't cry. Please don't cry. It'll be alright." Tadashi pleaded, wrapping Baymax's bulbous arms around the boy and holding him close. "I'm here, Hiro..."

Hiro let out a particularly loud sob and buried his face into Baymax's vinyl. "T-Ta-Tadashi..." He choked out. "I missed you s-so much..."

Tadashi could only hold his brother tighter, unable to cry with him due to Baymax's lack of that ability. "Shhh, Hiro. I'm here. I'm sorry I didn't listen to you. I'm sorry I ran into the fire. I'm sorry I left you and put you through so much pain. But I'm here now." The young man said softly.

Hiro didn't reply, only buried his face deeper into the soft material of Baymax. After a while, the boy calmed and his sobs subsided.

Tadashi slowly released his brother and stepped back. "Are you okay now?" He asked.

Hiro wiped his eyes and nodded. He looked up at the inflated bot and gave a shaky smile. "Its great to see you again, Tadashi..." He said.

Baymax's body was physically unable to smile, so Tadashi chuckled instead, "but you _can't_ see me. I'm a ghost."

Hiro nodded slowly and, now that his head was clearer, studied Baymax further. "So... How are you controlling Baymax?" He asked, poking at the bot's belly.

Tadashi tilted his head. "It must've been the chip." He said. Hiro looked confused, so he continued. "I had touched Baymax earlier while he was active, and nothing happened. But this time you took out his chip, which is his entire AI program, his _soul_. I'm thinking that because he no longer had that, it left room for something else to take over, so when I touched him, my soul automatically latched onto him and made him my vessel." Tadashi explained.

Hiro nodded his head. "That makes sense... In a weird sort of way..." He looked up at Tadashi and smiled. "So all you needed was an empty shell to possess?"

Baymax's body shivered. "Don't say it like that, it makes me sound like a demon possessing a victim..."

Hiro grinned at that. "Whatever you say, nerd." The boy then looked Baymax's body up and down. "If you can possess robots, then you can probably find a better container. I can even build you one if you'd like. Who knows what you're doing to Baymax's circuits." He suggested.

Tadashi blinked in surprise. He hadn't thought of that. It was a strange notion and if they went through with it there could be many complications. But... Tadashi really, _really_ wanted to have a body again, to interact with the world and the living, and Hiro was offering to make that happen. "That's... a pretty good idea, actually." The older Hamada said after a moment. "I don't want to risk messing with Baymax any more than I have already, so..." He ruffled Hiro's hair affectionately. "I'd love for you to make me a new body... As weird as that sounds..."

Hiro made a face at his brother's action and pulled away quickly, though he didn't really seem irritated at all. "Alright then. I'll start planning right away." He said excitedly, fixing his hair.

The boy turned toward his desk and froze. The computer was showing a little box that said 'download complete' on it. His eyes wandered to the green chip plugged into his computer with a wince. He'd forgotten about Baymax...

Tadashi placed a hand on Hiro's shoulder and the boy looked up at him. "It's okay, Hiro." The older brother said. "Plug Baymax back in. He can help you out with the plans and assembly."

Hiro looked stricken. "B-But... How will I be able to talk to you?" He asked.

Tadashi gave the boy's shoulder a reassuring squeeze. "I can write to you. I seem to be able to touch inanimate objects. Also, Baymax seems to be able to hear and see me for some reason so you can have him relay what I say to you. We don't have to talk face to face, Hiro. And besides, once you finish making me a body, we can talk for as long as you want, okay?" He said softly.

Hiro sniffled and nodded his head hesitantly. He walked over to his computer and plucked the chip from the device. He held the small green square in his palm for a moment before turning back to his brother's creation. With a shaky smile, Hiro opened the robot's empty access port.

"Ready, Tadashi?" The boy asked shakily.

Tadashi nodded and patted his little brother on the head. "Yeah. Go for it. I'll still be here, don't worry." He murmured.

Hiro nodded in reply and shakily raised the healthcare chip to the access port. Closing his eyes tight, he shoved it in and waited.

"Hello. I am Baymax, your personal healthcare companion. What can I do for you, Hiro?"

Hiro opened his eyes and looked up at the robotic nurse. He was staring at the boy with those black eyes that, while they had their own soul to them, Hiro knew his brother was no longer seeing through.

"Your neural transmitter levels have changed since my last scan. Did something happen while you were updating my chip?" Baymax asked in a concerned voice.

Hiro closed his eyes tight against his tears. Tadashi's spirit was no longer inside the bot. He couldn't talk to his brother... Then Hiro felt a light brush of warm air against his cheek, as if someone had touched him there. He smiled. Tadashi was still here.

"I'm fine, Baymax. And yes, a few things did happen while your chip was removed..."

Tadashi watched his little brother explain what they'd found out to Baymax from a few feet away, smiling happily.

Unbeknownst to the three of them, in the darkness under Hiro's bed, a tiny microbot twitched inside a sweatshirt pocket...

* * *

 _ ****(DUN DUN DUN! Oh no! How are they gonna stop Callaghan/Yokai if they don't even know he exists! It is a mystery! Krei, you gon' die. Probs. maybe. Not really. ANYWAY! I hope you enjoyed that crappy chapter! At least the smol noodle knows the big dorito bro is there with him. Yay!)****_

 _Please leave a review!_


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